Callus Induction, Proliferation, Enhanced Secondary Metabolites Production and Antioxidants Activity of Salvia moorcroftiana L. as Influenced by Combinations of Auxin, Cytokinin and Melatonin

HIGHLIGHTS

• Tissue culture technique is considered to be one of the best methods to reproduce salvia plant.

• Salvia is a medicinal plant with lots of chemical constituents.

• Salvia plays an important role in treating different fatal diseases.

• Maximum fresh and dry weights were obtained at 1.5 mg L^-1 melatonin.

• the highest DPPH scavenging activity, total phenolics and flavonoid content were obtained at 1.5 mg L^-1 melatonin.

Abstract:

Tissue culture technique is one of the best methods to reproduce salvia plant Therefore, the aim of this research was to enhance the in-vitro callus proliferation and production of secondary metabolites of S. moorcroftiana using different combinations of auxin, cytokinin and melatonin. Initially, callus induction was optimized using indole acetic acid (IAA), 2, 4-dichlorophenoxy acetic acid (2,4-D), and naphthalene acetic acid (NAA) applied at different concentrations in combination with 1 mg L^-1 of 6-benzylaminopurine (BAP). The results indicates that earliest days to callus induction (14.67 days) was occurred in the media fortified with 2, 4-D+BAP (2.0+1.0 mgL-1). Whereas the highest callus initiation (100%) was induced on MS medium incorporated with 2,4-D+BAP (1+1mgL^-1). Furthermore, maximum fresh weight was obtained when 2,4- D + BAP at the rate of (1+ 1mg L^-1) was incorporated and dry weight was attained when 2,4- D + BAP at the rate of (2+1 mg L^-1) was added to MS media. The maximum fresh and dry weight was obtained when melatonin at rate of 1.5 mg L^-1 was supplemented with MS media including 2,4-D + BAP (1+1mg L^-1), moreover the maximum DPPH scavenging activity, total phenolic and flavonoid content was noted when supplemented with melatonin at rate of 1.5 mg L^-1. In conclusion, among various concentrations of plant growth regulators, 2,4- D + BAP at the rate of (1+ 1mg L^-1) along with 1.5 g L^-1 melatonin was the best for callus growth and production of secondary metabolites of S. moorcroftiana.

Keywords:
Antioxidant activity; Growth regulators; Sage; Secondary Metabolites